Ultrasensitive Urinary Diagnosis of Organ Injuries Using Time-Resolved Luminescent Lanthanide Nano-bioprobes.

Urinary sensing of synthetic biomarkers that are released into urine after specific activation in an in vivo disease environment is an emerging diagnosis strategy to overcome the insensitivity of a previous biomarker assay. However, it remains a great challenge to achieve sensitive and a specific urinary photoluminescence (PL) diagnosis. Herein, we report a novel urinary time-resolved PL (TRPL) diagnosis strategy by exploiting europium complexes of diethylenetriaminepentaacetic acid (Eu-DTPA) as synthetic biomarkers and designing the activatable nanoprobes.

Unveiling Local Electronic Structure of Lanthanide-Doped Cs NaInCl Double Perovskites for Realizing Efficient Near-Infrared Luminescence.

Lanthanide ion (Ln )-doped halide double perovskites (DPs) have evoked tremendous interest due to their unique optical properties. However, Ln ions in these DPs still suffer from weak emissions due to their parity-forbidden 4f-4f electronic transitions. Herein, the local electronic structure of Ln -doped Cs NaInCl DPs is unveiled.

Polarity-dependent emission from hydroxyl-free carbon nanodots.

Surface groups of carbon nanodots (CNDs) play a key role in modulating their photoluminescence (PL) properties. However, most of the as-prepared CNDs are complex mixtures of CNDs bearing different surface groups. Thus, the purification of CNDs is essential to reveal the PL mechanism of CNDs.

Boosting Near-Infrared Luminescence of Lanthanide in Cs AgBiCl Double Perovskites via Breakdown of the Local Site Symmetry.

Currently, lanthanide (Ln )-doped near-infrared (NIR)-emitting double perovskites (DPs) suffer from low photoluminescence quantum yield (PLQY). Herein, we develop a new class of NIR-emitting DPs based on Ln -doped Cs (Na/Ag)BiCl . Benefiting from the Na -induced breakdown of local site symmetry in the Cs AgBiCl DPs, effective NIR emissions of Ln are realized through Bi sensitization.

Thermally boosted upconversion and downshifting luminescence in Sc(MoO):Yb/Er with two-dimensional negative thermal expansion.

Rare earth (RE)-doped phosphors generally suffer from thermal quenching, in which their photoluminescence (PL) intensities decrease at high temperatures. Herein, we report a class of unique two-dimensional negative-thermal-expansion phosphor of Sc(MoO):Yb/Er. By virtue of the reduced distances between sensitizers and emitters as well as confined energy migration with increasing the temperature, a 45-fold enhancement of green upconversion (UC) luminescence and a 450-fold enhancement of near-infrared downshifting (DS) luminescence of Er are achieved upon raising the temperature from 298 to 773 K.

Tumor-Microenvironment-Responsive Biodegradable Nanoagents Based on Lanthanide Nucleotide Self-Assemblies toward Precise Cancer Therapy.

Stimuli-responsive nanoagents, which simultaneously satisfy normal tissue clearance and tumor-specific responsive treatment, are highly attractive for precise cancer theranostics. Herein, we develop a unique template-induced self-assembly strategy for the exquisitely controlled synthesis of self-assembled lanthanide (Ln ) nucleotide nanoparticles (LNNPs) with amorphous structure and tunable size from sub-5 nm to 105 nm. By virtue of the low-temperature (10 K) and high-resolution spectroscopy, the local site symmetry of Ln in LNNPs is unraveled for the first time.

Boosting the Self-Trapped Exciton Emission in Alloyed Cs (Ag/Na)InCl Double Perovskite via Cu Doping.

Fundamental understanding of the effect of doping on the optical properties of 3D double perovskites (DPs) especially the dynamics of self-trapped excitons (STEs) is of vital importance for their optoelectronic applications. Herein, a unique strategy via Cu doping to achieve efficient STE emission in the alloyed lead-free Cs (Ag/Na)InCl DPs is reported. A small amount (1.

Enhancing Dye-Triplet-Sensitized Upconversion Emission Through the Heavy-Atom Effect in CsLu F :Yb/Er Nanoprobes.

Lanthanide (Ln )-doped upconversion (UC) nanoprobes, which have drawn extensive attention for various bioapplications, usually suffer from small absorption cross-sections and weak luminescence intensity of Ln ions. Herein, we report the controlled synthesis of a new class of Ln -doped UC nanoprobes based on CsLu F :Yb/Er nanocrystals (NCs), which can effectively increase the intersystem crossing (ISC) efficiency from singlet excited state to triplet excited state of IR808 up to 99.3 % through the heavy atom effect.

Unusual Temperature Dependence of Bandgap in 2D Inorganic Lead-Halide Perovskite Nanoplatelets.

Understanding the origin of temperature-dependent bandgap in inorganic lead-halide perovskites is essential and important for their applications in photovoltaics and optoelectronics. Herein, it is found that the temperature dependence of bandgap in CsPbBr perovskites is variable with material dimensionality. In contrast to the monotonous redshift ordinarily observed in bulk-like CsPbBr nanocrystals (NCs), the bandgap of 2D CsPbBr nanoplatelets (NPLs) exhibits an initial blueshift then redshift trend with decreasing temperature (290-10 K).

The effect of surface-capping oleic acid on the optical properties of lanthanide-doped nanocrystals.

The rapid development of nanotechnology has placed a higher demand on the synthesis of nanomaterials. Benefiting from its capability to keep nanoparticles away from aggregation, oleic acid (OA) has been routinely utilized as a capping agent in the synthesis of monodisperse nanocrystals. To satisfy downstream biological applications, hydrophobic OA capping on the surface should be removed or coated, but scarce attention has been paid to its influence on the optical properties of nanocrystals.

Enhancing multiphoton upconversion emissions through confined energy migration in lanthanide-doped CsNaYF nanoplatelets.

Lanthanide (Ln3+)-doped upconversion (UC) nanocrystals have drawn tremendous attention because of their intriguing optical properties. Currently, it is highly desired but remains challenging to achieve efficient multiphoton UC emissions. Herein, we report the controlled synthesis of a new class of UC nanocrystals based on Cs2NaYF6:Yb/Tm nanoplatelets (NPs), which can effectively convert the 980 nm light to five-photon and four-photon UC emissions of Tm3+ without the fabrication of a complicated core/multishell structure required in traditional nanocrystals.

Ultrasensitive Point-of-Care Test for Tumor Marker in Human Saliva Based on Luminescence-Amplification Strategy of Lanthanide Nanoprobes.

The point-of-care detection of tumor markers in saliva with high sensitivity and specificity remains a daunting challenge in biomedical research and clinical applications. Herein, a facile and ultrasensitive detection of tumor marker in saliva based on luminescence-amplification strategy of lanthanide nanoprobes is proposed. EuO nanocrystals are employed as bioprobes, which can be easily dissolved in acidic enhancer solution and transform into a large number of highly luminescent Eu micelles.

Recent advances in design of lanthanide-containing NIR-II luminescent nanoprobes.

Luminescent biosensing in the second near-infrared window (NIR-II, 1000-1700 nm) region, which has weak tissue scattering and low autofluorescence, draws extensive attention owing to its deep tissue penetration, good spatial resolution and high signal-to-background ratio. As a new generation of NIR-II probes, lanthanide (Ln)-containing nanoprobes exhibit several superior properties. With the rapid development of Ln-containing NIR-II nanoprobes, many significant advances have been accomplished in their optical properties tuning and surface functional modification for further bioapplications.

Engineering the Bandgap and Surface Structure of CsPbCl Nanocrystals to Achieve Efficient Ultraviolet Luminescence.

Herein, we report the design of novel ultraviolet luminescent CsPbCl nanocrystals (NCs) with the emission peak at 381 nm through doping of cadmium ions. Subsequently, a surface passivation strategy with CdCl is adopted to improve their photoluminescence quantum yield (PLQY) with the maximum value of 60.5 %, which is 67 times higher than that of the pristine counterparts.

Energy transfer designing in lanthanide-doped upconversion nanoparticles.

Lanthanide (Ln3+)-doped upconversion nanoparticles (UCNPs), exhibiting excellent optical properties such as long photoluminescence lifetime, narrow emission bandwidth, and low autofluorescence background, have been applied in many fields, especially in biological analysis and medical diagnostics. Despite the exciting progress, the applications of Ln3+-doped UCNPs are hindered by the small absorption cross-section and low upconversion luminescence efficiency of Ln3+. To this regard, several effective strategies associated with energy transfer designing have been proposed to modulate the upconversion luminescence properties of Ln3+ in the past few decades.

A Dual-Excitation Decoding Strategy Based on NIR Hybrid Nanocomposites for High-Accuracy Thermal Sensing.

Optical thermal sensing holds great promise for disease theranostics. However, traditional ratiometric thermometry methods, in which intensity ratio of two nonoverlapping emissions is defined as the thermosensitive parameter, may have a limited accuracy in temperature read-out due to the deleterious interference from wavelength- and temperature-dependent photon attenuation in tissue. To overcome this limitation, a dual-excitation decoding strategy based on NIR hybrid nanocomposites comprising self-assembled quantum dots (QDs) and Nd doped fluoride nanocrystals (NCs) is proposed for thermal sensing.

Luminescent lanthanide metal-organic framework nanoprobes: from fundamentals to bioapplications.

Metal-organic frameworks (MOFs), a unique type of porous material characterized by high porosity, large internal surface area and remarkable structural tunability, have emerged as very attractive functional materials for a variety of applications. As a promising subclass of MOFs, lanthanide metal-organic frameworks (Ln-MOFs) integrate the unique advantages of MOFs and the intrinsic features of lanthanide ions, such as sharp emission bands, long luminescent lifetimes, large Stokes shifts, high color purity and high resistance to photobleaching. In this minireview, we provide a brief overview of the most recent advances in luminescent Ln-MOF nanoprobes, which covers from their chemical and physical fundamentals to bioapplications, including their synthetic strategies, optical properties and promising bioapplications in biodetection, bioimaging and therapy.

Revisiting the Luminescence Decay Kinetics of Energy Transfer Upconversion.

Energy transfer upconversion (ETU) can efficiently upconvert near-infrared photons into higher-energy photons. Although a comprehensive understanding of ETU is fundamental to the design of ETU materials, the basic excited-state decay kinetics of ETU remains a complicated problem. Here we unravel the mechanism underlying ETU decay in benchmark β-NaYF:Er and β-NaYF:Ln/Yb (Ln = Er, Ho, Tm) ETU microcrystals by combining rate equation analyses with ETU decay measurements.

Accurate detection of β-hCG in women's serum and cervical secretions for predicting early pregnancy viability based on time-resolved luminescent lanthanide nanoprobes.

Sensitive and specific detection of β-hCG in women's serum and cervical secretions is of great significance for early pregnancy evaluation. However, the accurate detection of trace amounts of β-hCG in cervical secretions remains challenging because of its low level. Herein, we report a unique strategy for β-hCG detection in a heterogeneous sandwich-type bioassay by using LiLuF:Ce,Tb nanoparticles as time-resolved photoluminescence (PL) nanoprobes.